Morphological and functional abnormalities pattern in hypertrophy-free HCM mutation carriers detected with echocardiography.

To evaluate if morphological or functional abnormalities could be detected with echocardiography in hypertrophic myocardiopathy (HCM) mutation carriers without left ventricle (LV) hypertrophy has developed. HCM is caused by extensive genes mutations found in two-third of patients. Because screening for carriership of a large population is unreasonable, identification of asymptomatic subjects is confined to the use of imaging such as echocardiography, by which subtle abnormalities can be detected. Comprehensive echocardiographic studies including morphological and functional assessment were performed. Asymptomatic HCM mutation carriers without hypertrophy (Phe-/Gen+, n = 14), and HCM patients (Phe+/Gen+, n = 17) were compared with healthy control subjects (n = 32) in a prospective design. Compared to controls, septum thickness was significantly higher with an elongated mitral valve in both groups. Thickened LV muscular band (LVMB) are more likely found in Phe-/Gen+ and Phe+/Gen+. The thickness of LVMB was higher in the Phe-/Gen+ versus controls. A LVMB thickness ≥3.6 mm was associated with HCM mutation carriership (sensitivity: 76.9 %, specificity: 94.1 %). The regional strain was significantly impaired in the basal segments of the septum in the Phe-/Gen+. The GLS was significantly impaired in the Phe+/Gen+ (-16.4 % ± 2.9 vs. -21.4 % ± 2.3 in control subjects, p = 0.01). Mitral A wave velocity, septal E/e', averaged E/e' were increased in both groups. E/A ratio was significantly lower in Phe+/Gen+. Morphological and functional abnormalities in hypertrophy-free HCM mutation carriers could be detected with echocardiography. Anomalous thickened LVMB could be representing a morphological marker for the HCM disease without overt hypertrophy has developed or in patients with an ambiguous diagnosis.

Abnormal left ventricular contraction sequence in hypertrophic cardiomyopathy patients: first description of hypersynchrony and invert synchrony.

The aim of this study was to compare left ventricular contraction sequence in patients with hypertrophic cardiomyopathy (HCM) and healthy controls. Normal left ventricular contraction sequence in healthy controls exhibits an apex-to-base delay (ABD) contributing to efficient cardiac mechanics (physiologic asynchrony). Echocardiographic data from 20 controls and 40 HCM patients were prospectively analyzed. Endocardial longitudinal and circumferential strains and ABD were measured using custom-built software. HCM patients had increased circumferential (-36.4 ± 6.0 vs. -32.9 ± 5.0, p < 0.01) and decreased longitudinal (-19.3 ± 6.4 vs. -23.4 ± 5.7, p < 0.01) strains. In controls, physiologic ABD was observed (35.7 ± 18.1 ms). This delay was reduced in HCM patients (5.5 ± 22.7 ms, p < 0.01 vs. controls). There was no interaction between ABD and common clinical or echocardiographic parameters in the HCM population. Left ventricular contraction sequence can be modified in HCM patients, with the loss of the physiologic ABD. This phenomenon is independent from commonly measured parameters.

Clinical and imaging description of the Maron subtypes of hypertrophic cardiomyopathy.

Longitudinal strain analysis enables early detection of left ventricular (LV) contraction abnormalities in patients with preserved ejection fraction. Hypertrophic cardiomyopathy (HCM) is associated with low values of regional and global longitudinal myocardial deformations. In addition to contraction abnormalities, LV regional strain abnormalities are partially related to the degree of hypertrophy. This study sought to describe global longitudinal strain (GLS) in HCM patients as categorized using the Maron's classification. Complete echocardiography examinations, including GLS analysis, were performed in consecutive HCM patients followed up in two French HCM-clinics. A total of 271 patients (mean age 49 ± 16yrs; 71 % male) were evaluated. In this population, the most frequently classified hypertrophy pattern was Type II (47 %), following the Maron's classification. Type III was characterized by a higher degree of LV hypertrophy in terms of mass and maximal wall thickness, and was more frequently obstructive at rest, with lower GLS values (-15.3 ± 3.9 %, p = 0.016), higher E/E' ratio (13.4 ± 6.7, p < 0.001), and a more frequently inadequate blood pressure response to exercise (30 %, p = 0.04) compared to other patterns. The variable that correlated best with GLS was LV mass index (r = 0.49, p < 0.01), while GLS did not significantly correlate with left ventricular outflow tract obstruction. This study demonstrated that the Type III HCM pattern presented with lower GLS, which was partially related to higher LV mass index, more elevated LV filling pressures, and a more frequently inadequate blood pressure response to exercise, in comparison with other patterns categorized using the Maron's classification.

Comparison of resting and exercise echocardiographic parameters as indicators of outcomes in hypertrophic cardiomyopathy.

BACKGROUND: Both resting echocardiography and exercise echocardiography produce variables predictive of outcomes in patients with hypertrophic cardiomyopathy (HCM). The aim of the present study was to compare the respective value of resting and exercise echocardiographic parameters as indicators of clinical outcomes in patients with HCM. METHODS: Resting and exercise echocardiography was performed prospectively in patients with HCM evaluated at the HCM Competence Center of Bordeaux and followed up every 6 months. A composite cardiac event was defined. RESULTS: One hundred fifteen patients (mean age, 51.9 ± 15.2 years; 66% men) were evaluated by echocardiography and followed for a mean period of 19 ± 11 months. Eighteen patients (16%) reached the composite end point, including 10 progressions to New York Heart Association functional class III or IV. On rest echocardiography, in patients with cardiac events during follow-up, left atrial volume index was significantly more increased, as were lateral E/E' ratio and left ventricular outflow tract (LVOT) gradient, whereas mean global longitudinal strain (GLS) expressed in magnitude (14.0 ± 2.6% vs 17.0 ± 3.6%, P < .001) and peak velocities at the lateral annulus by Doppler tissue imaging were significantly reduced compared with patients without events. At peak exercise, patients who developed cardiac events were characterized by lower ejection fractions and greater LVOT gradients (76 ± 55 mm Hg vs 40 ± 40 mm Hg, P < .002). A Cox backward-entry selection model revealed that GLS ≤ 15% at rest and LVOT gradient ≥ 50 mm Hg at peak exercise were independently associated with an increased risk for poor outcomes in patients with HCM (hazard ratios, 3.8 [P = .017] and 3.3 [P = .028], respectively). On Kaplan-Meier survival analyses, peak exercise LVOT gradient evaluation showed additive value to predict outcomes, particularly in patients with rest GLS > 15% (log-rank P = .001) and despite a resting LVOT gradient ≥ 30 mm Hg (log-rank P = .001). CONCLUSION: This study supports the value of resting GLS and of peak LVOT gradient, measured during exercise echocardiography, in identifying patients with HCM at increased risk for adverse events during follow-up.

Evaluation of global left ventricular systolic function using three-dimensional echocardiography speckle-tracking strain parameters.

BACKGROUND: The aim of this study was to evaluate the capacity and reproducibility of three-dimensional echocardiographic (3DE) strain parameters in the assessment of global left ventricular (LV) systolic function. METHODS: A total of 128 subjects with differing LV ejection fractions were investigated using two-dimensional echocardiographic (2DE) and 3DE strains. Three-dimensional echocardiographic strain allows obtaining longitudinal, circumferential, radial, and area strains. First, values of global longitudinal strain (GLS) by 2DE and 3DE speckle-tracking analyses were compared. Thereafter, 3DE strain parameters were correlated with LV ejection fraction and indexed output. Last, the variability of 3DE versus 2DE strain measurements as well as recorded time of analysis were assessed. RESULTS: After excluding 21 patients for insufficient image quality, four for arrhythmia, two for severe valvular disease, and one for severe dyspnea, the final population consisted of 100 patients. Comparison between 2DE and 3DE GLS revealed high correspondence (r = 0.91, y = 1.04x - 0.71) and mean error measurement of -1.3% (95% confidence interval, -5.7 to 3.2). Among strain parameters, global area strain exhibited the highest correlation with LV ejection fraction (y = -1.65 + 10.4, r = -0.92, P < .001). Intraobserver measurement variability proved acceptable: 8% for GLS (vs 6% on 2DE analysis), 7% for circumferential strain (vs 15% on 2DE analysis), 7% for radial strain (vs 33% on 2DE analysis), and 5% for global area strain. The mean error between two measurements was lower with 3DE than 2DE analysis for circumferential and radial strains but similar for GLS. The mean time of analysis was of 117 ± 16 sec for 3DE analysis, which was 25% less than for 2DE analysis (P < .001). CONCLUSIONS: Of all strain parameters, new 3DE area strain correlated best with common LV systolic function parameters and is thus the most promising approach, while all 3DE strain markers exhibited good reproducibility.

Robustness of a new three-dimensional echocardiographic algorithm for left ventricular volume and ejection fraction quantification: experts vs. novices.

AIMS: We evaluated the ability of a new simplified algorithm for three-dimensional echocardiography (3DE) left ventricular (LV) measurements with minimal operator interaction to be reproducible and robust, independently of the experience. METHODS AND RESULTS: A total of 163 subjects were investigated using two-dimensional echocardiography (2DE) and 3DE. The 3D data sets were blindly analysed offline by novice investigators and experts. A subgroup of 30 patients was assessed using cardiac magnetic resonance imaging (CMRI) to compare end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) obtained by 2DE, 3DE, and CMRI. Intra-observer and inter-observer variabilities of 2DE and 3DE measurements were evaluated according to level of experience. Mean time analysis of 3DE data was 23.2 ± 6.3s for the novice and 26.1 ± 4.1 s for the expert (P = ns). Correlations (r) and mean error measurements (MEM) between 3DE analysis by experts and novices were 0.91 and -3.5 mL for EDV, 0.97 and 4.3 mL for ESV, and 0.91 and -2.6% for EF, respectively. Correlations between 3DE and CMRI were good with low variability and greater agreement when compared with those between 2DE and CMRI. For the novice, MEM was -21.3 mL for EDV, -15.0 mL for ESV, and 2.3% for EF. MEM and 95% confidence intervals were wider for 2DE vs. CMRI than for 3DE vs. CMRI in relation to both expert and novice. CONCLUSION: This new semi-automated algorithm of LV endocardial border detection based on 3DE data appears suitable for clinical use by either expert or novice investigators with greater reproducibility and time of analysis than 2DE.